Business Combinations and Discontinued Operations - Consolidated statements (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	May 05, 2018	Feb. 03, 2018	Feb. 03, 2018	Jan. 28, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of business			$ 1,262	$ 11,337
Net (loss) income from discontinued operations
Net (loss) income from discontinued operations			(128)	828
Carrying amounts of assets and liabilities included in discontinued operations
Current assets of discontinued operations		$ 1,868	1,868	12,032
Noncurrent assets of discontinued operations				903
Hi-Tec sales and distribution business | Disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales and distribution business		3,100	3,100
Cash proceeds from sale of business		1,300
Net (loss) income from discontinued operations
Product sales and royalty revenues			19,492	6,599
Cost of goods sold			15,106	5,083
Selling, general and administrative expenses			4,384	688
Depreciation and amortization			167
Pretax (loss) income from discontinued operations			(165)	828
Gain on disposal of discontinued operations			37
Total pretax (loss) income from discontinued operations			(128)	828
Net (loss) income from discontinued operations			(128)	828
Carrying amounts of assets and liabilities included in discontinued operations
Accounts receivable and amounts due from sale of business		1,868	1,868	10,465
Inventories				1,567
Current assets of discontinued operations		1,868	1,868	12,032
Intangible asset—Distributor relationships				492
Goodwill				400
Property and equipment				11
Noncurrent assets of discontinued operations				903
Accounts payable and other accrued liabilities		1,103	1,103	4,083
Net assets of discontinued operations		$ 765	$ 765	$ 8,852
Subsequent Event | Hi-Tec sales and distribution business | Disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of business	$ 1,800